lkml.org 
[lkml]   [2002]   [Jul]   [8]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
/
Date
From
SubjectRe: pipe and af/unix latency differences between aa and jam on smp

On 2002.07.09 rwhron@earthlink.net wrote:
>The -jam patchset is interesting because it starts out
>with the entire -aa patchset and adds a few things.
>
>Sometimes small differences in LMbench between -jam and -aa are
>just CPU bounces on SMP. The difference for pipe and af/unix latency
>only appears on SMP too, but it is very consistent. (My k6/2
>has small differences between -aa and -jam for pipe and af/unix
>latency).
>
>You will know better what could make the difference:
>
>This is the averages:
>
>*Local* Communication latencies in microseconds - smaller is better
>-------------------------------------------------------------------
>kernel Pipe AF/Unix
>----------------- ------- -------
>2.4.19-pre10-aa4 33.941 70.216
>2.4.19-pre10-jam2 7.877 16.699
>

I took a look at your numbers:

*Local* Communication latencies in microseconds - smaller is better
-------------------------------------------------------------------
kernel Pipe AF/Unix UDP RPC/UDP TCP RPC/TCP TCPconn
----------------------------- ------- ------- ------- ------- ------- ------- -------
2.4.19-pre7-jam6 29.513 42.369 58.6165 60.7792 50.2572 82.4976 87.321
2.4.19-pre8-jam2 7.697 15.274 59.6730 60.8190 55.276 82.1297 89.416
2.4.19-pre8-jam2-nowuos 7.739 14.929 57.9326 60.5497 55.9745 81.8908 90.370

(last line says that wake-up-sync is not responsible...)

Main changes between first two were irqbalance and ide6->ide10.


--
J.A. Magallon \ Software is like sex: It's better when it's free
mailto:jamagallon@able.es \ -- Linus Torvalds, FSF T-shirt
Linux werewolf 2.4.19-rc1-jam2, Mandrake Linux 8.3 (Cooker) for i586
gcc (GCC) 3.1.1 (Mandrake Linux 8.3 3.1.1-0.7mdk)
-
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@vger.kernel.org
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/

\
 
 \ /
  Last update: 2005-03-22 13:27    [W:0.063 / U:0.120 seconds]
©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site